Abstract: The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a C02-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Abstract: A column-conditioning enclosure includes a column chamber adapted to hold one or more chromatography separation columns. A duct system provides an airflow path around the column chamber such that the one or more chromatography separation columns held within the column chamber are isolated from the airflow path. An air mover disposed in the airflow path generates a flow of air within the duct system. A heat exchanger system disposed in the airflow path near the air to exchange heat with the air as the air flows past the heat exchanger system. The air circulates through the duct system around the column chamber, convectively exchanging heat with the column chamber to produce a thermally conditioned environment for the one or more chromatography separation columns held within the column chamber.

Abstract: The invention provides compression fittings and methods of assembling compression fittings. In exemplary embodiments, compression fittings are provided that include a fitting body, a ferrule and a tube. For example, the fitting body can be removably coupled to the ferrule when the tube is disposed therethrough.

Abstract: A liquid chromatography system includes a pumping system with a selector valve in fluidic communication with a pump inlet. The selector valve switches between a first position, in which the selector valve fluidically couples a solvent reservoir to the pump inlet, and a second position, in which the selector valve fluidically couples a pressurized source of liquefied carbon dioxide (for example) to the pump inlet. The liquid chromatography system can perform as a HPLC system (or as an UPLC system) when the selector valve is in the first position and as a CO2-based chromatography system when the selector valve is in the second position. The selector valve can have a third position in which both the fluidic pathway between the solvent reservoir and the pump inlet and the fluidic pathway between the pressurized source and the pump inlet are blocked. This shut-off position advantageously facilitates system maintenance.

Abstract: The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a C02-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Abstract: The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a CO2-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Abstract: A method for detecting a fluid leak in a vacuum chamber of a degasser is provided. The method includes measuring a temperature of the vacuum chamber with a temperature sensing device, wherein a temperature drop of the vacuum chamber indicates the fluid leak within the vacuum chamber. An associated degasser and further methods are also provided.

Abstract: Systems and methods for pumping carbon dioxide in a chromatography system include an actuator that receives and compresses carbon dioxide at or above room temperature at a given pressure to put the carbon dioxide in or near supercritical form. This actuator can be a pre-pump disposed on the intake side of a pumping system. Alternatively, this actuator can be a primary actuator in the pumping system. The actuator includes an intake chamber that receives the carbon dioxide and a movable plunger extending into and closely received by the intake chamber. The plunger has a diameter and stroke length adapted to compress the carbon dioxide received by the intake chamber in sufficient volume at the given pressure to put the carbon dioxide in or near supercritical form at or above room temperature. A metered amount of the carbon dioxide in or near supercritical form can then be pumped.

Abstract: A passive pre-heater assembly includes a thermally conductive heat-spreading block and a plurality of passive pre-heaters in thermally conductive communication with the heat-spreading block. The plurality of the pre-heaters exchanges heat with the thermally conductive heat-spreading block. Each pre-heater includes a thermally conductive base in thermal communication with the heat-spreading block, and a plurality of thermally conductive fins is in thermal communication with the thermally conductive base. The plurality of fins of each pre-heater exchanges heat convectively with ambient air and conductively with the thermally conductive base of that pre-heater. A given one of the passive pre-heaters further comprises a tube in thermally conductive contact with the thermally conductive base of the given passive pre-heater. The thermally conductive heat-spreading block exchanges heat with a fluid passing through the tube of the given passive pre-heater.

Abstract: An apparatus for use in a liquid chromatography system includes a chromatography port and a tubing assembly having a chromatography tube coupled at one end to the chromatography port. The end of the tube has an end face covered with a corrosion-resistant material, for example, gold. The corrosion-resistant nature of the material protects the end of the tube from corrosion or erosion, which improves the quality and reliability of a seal between the end face of the tube and a sealing surface of the port. Alternatively, or in addition to covering the end face of the tube with the corrosion-resistant material, a gasket covered with or made of the corrosion-resistant material can be disposed between the end face of the tube and the port. This gasket extends the reach of the tube to facilitate bottoming out the tube within the port.

Abstract: The present disclosure relates to methodologies, systems and apparatus for cooling pump heads and providing balanced cooling and heat transfer between multiple pump heads. Multi-pump systems that are used to pump fluids that vary greatly in density with minor changes in temperature, such as the mobile phase of a C02-based chromatography system, require highly stable temperature conditions. In order to achieve a substantially equal average heat transfer between multiple pump heads and a coolant fluid, coolant fluid may be flowed through coolant passageways within the pump heads in a recursive and/or parallel coolant flow patterns. Such recursive and/or parallel coolant fluid flow patterns provide increased stability in temperature, compressibility, and density of the fluids passing through a multi-pump system.

Abstract: A method for controlling fluid flowing through a chromatographic system includes determining a fluidic parameter related to density at a first fluidic location in the chromatographic system; and in response to the determined fluidic parameter, modifying a volumetric flow rate or a pressure at a second fluidic location in the chromatographic system to produce a selected mass flow rate of the fluid.

Abstract: The invention provides compression fittings and methods of assembling compression fittings. In exemplary embodiments, compression fittings are provided that include a fitting body, a ferrule and a tube. For example, the fitting body can be removably coupled to the ferrule when the tube is disposed therethrough.

Abstract: A column-conditioning enclosure includes a column chamber adapted to hold one or more chromatography separation columns. A duct system provides an airflow path around the column chamber such that the one or more chromatography separation columns held within the column chamber are isolated from the airflow path. An air mover disposed in the airflow path generates a flow of air within the duct system. A heat exchanger system disposed in the airflow path near the air to exchange heat with the air as the air flows past the heat exchanger system. The air circulates through the duct system around the column chamber, convectively exchanging heat with the column chamber to produce a thermally conditioned environment for the one or more chromatography separation columns held within the column chamber.

Abstract: A passive pre-heater assembly includes a thermally conductive heat-spreading block and a plurality of passive pre-heaters in thermally conductive communication with the heat-spreading block. The plurality of the pre-heaters exchanges heat with the thermally conductive heat-spreading block. Each pre-heater includes a thermally conductive base in thermal communication with the heat-spreading block, and a plurality of thermally conductive fins is in thermal communication with the thermally conductive base. The plurality of fins of each pre-heater exchanges heat convectively with ambient air and conductively with the thermally conductive base of that pre-heater. A given one of the passive pre-heaters further comprises a tube in thermally conductive contact with the thermally conductive base of the given passive pre-heater. The thermally conductive heat-spreading block exchanges heat with a fluid passing through the tube of the given passive pre-heater.

Abstract: An actuator has a support plate, a pump head in thermally conductive contact with the support plate, and an actuator body. Cooling means is disposed between the support plate and the actuator body. The cooling means is configured to remove and transfer heat from the pump head to the actuator body. In one embodiment, the cooling means includes two thermally conductive plates (called cold-side and hot-side plates) and a thermoelectric device disposed in thermally conductive contact between the cold-side and hot-side plates. The cold-side plate is in thermal communication with the pump head through the support plate. The hot-side plate is in thermal communication with the actuator body. The thermoelectric device is configured to transfer heat from the cold-side plate, which is in thermal communication with the pump head, to the hot-side plate, which is in thermal communication with the actuator body, thereby removing heat from the pump head.

Abstract: The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system.

Abstract: Systems and methods for pumping carbon dioxide in a chromatography system include an actuator that receives and compresses carbon dioxide at or above room temperature at a given pressure to put the carbon dioxide in or near supercritical form. This actuator can be a pre-pump disposed on the intake side of a pumping system. Alternatively, this actuator can be a primary actuator in the pumping system. The actuator includes an intake chamber that receives the carbon dioxide and a movable plunger extending into and closely received by the intake chamber. The plunger has a diameter and stroke length adapted to compress the carbon dioxide received by the intake chamber in sufficient volume at the given pressure to put the carbon dioxide in or near supercritical form at or above room temperature. A metered amount of the carbon dioxide in or near supercritical form can then be pumped.

Abstract: A method for controlling fluid flowing through a chromatographic system includes determining a fluidic parameter related to density at a first fluidic location in the chromatographic system; and in response to the determined fluidic parameter, modifying a volumetric flow rate or a pressure at a second fluidic location in the chromatographic system to produce a selected mass flow rate of the fluid.

Abstract: The present disclosure relates to phase detection in multi-phase fluids where two fluid phases can be present in the fluid. Phase detection apparatus and methods are disclosed for determining the phase(s) (e.g., supercritical, liquid, and/or gas) of a fluid in a multi-phase fluid system, such as carbon dioxide based separation and chromatography system.